4A12X4ZMonitoring of Cardiac Electrical Activity, External Approach

Measurement and Monitoring›Physiological Systems›Monitoring
  • Billable / Specific Code
ICD-10-PCS 4A12X4Z
CMS Source: FY 2027 ICD-10-PCS dataset. Effective Oct 1, 2026 – Sep 30, 2027.FacebookXLinkedInPrint

4A12X4Z is a billable ICD-10-PCS procedure code for Monitoring of Cardiac Electrical Activity, External Approach. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027). The root operation Monitoring involves determining the level of a physiological or physical function repetitively over a period of time. The Alphabetic Index lists this code under Telemetry. In AHRQ's Clinical Classifications Software (CCSR), this procedure falls under Cardiac monitoring.

Code Identity

ICD-10-PCS Code
4A12X4Z
Billable Status
Yes — Valid for Submission
Code Describes
Monitoring of Cardiac Electrical Activity, External Approach
Short Description
Monitoring of Cardiac Electrical Activity, External Approach
Same as the full description in the CMS dataset.
Parent Code
4A1

PCS Table Breakdown

Each ICD-10-PCS code is built from seven characters, each an axis of the procedure. Hover or tap the icons for the official CMS definitions.

PositionDesignationValueMeaning
1Section4Measurement and Monitoring
2Body SystemAPhysiological Systems
3Operation1Monitoring
4BodySystem2Cardiac
5ApproachXExternal
6Function/Device4Electrical Activity
7QualifierZNo Qualifier

In the ICD-10-PCS Alphabetic Index

The FY 2027 ICD-10-PCS Alphabetic Index refers to 4A12X4Z as Telemetry. These index entries lead to this code:

Telemetry
Direct entry for this code
Monitoring, Cardiac, Electrical Activity, No Qualifier
Direct entry for this code
Monitoring, Cardiac, Rate
Leads to this code's table
Monitoring, Cardiac, Sound
Leads to this code's table
Monitoring, Cardiac, Output
Leads to this code's table
Monitoring, Cardiac, Rhythm
Leads to this code's table
Monitoring, Cardiac, Electrical Activity
Leads to this code's table
SPY PINPOINT fluorescence imaging system
Leads to this code's table
Intravascular fluorescence angiography (IFA)
Leads to this code's table
SPY system intravascular fluorescence angiography
Leads to this code's table
Testing, Neurophysiologic monitoring, intra-operative
Leads to this code's table
Angiocardiography, SPY system intravascular fluorescence
Leads to this code's table
Assessment, Intravascular perfusion, using indocyanine green (ICG) dye
Leads to this code's table

To code telemetry, open the FY 2027 ICD-10-PCS Alphabetic Index at Telemetry. The entry lists 4A12X4Z directly as a complete, billable code.

Browse the full ICD-10-PCS Alphabetic Index →

Clinical Classification (CCSR)

AHRQ groups this procedure code into these clinical categories.

MAM008
Cardiac monitoring
Clinical domain: Measurement and Monitoring

Convert to ICD-9-PCS

Closest ICD-9-PCS equivalents for this code under the General Equivalence Mappings.

89.54
Electrographic monitoring
Approximate match.
89.57
Apexcardiogram (with ECG lead)
Approximate match.

Similar Procedure Codes

Questions About 4A12X4Z

Is 4A12X4Z a billable code?

Yes. This is a complete seven-character ICD-10-PCS code, specific enough to report Monitoring of Cardiac Electrical Activity, External Approach on inpatient claims from October 1, 2026 through September 30, 2027.

What is the ICD-10-PCS code for telemetry?

The ICD-10-PCS Alphabetic Index lists Telemetry under code 4A12X4Z, Monitoring of Cardiac Electrical Activity, External Approach, billable on inpatient claims in fiscal year 2027.

What do the characters in 4A12X4Z mean?

The code breaks down character by character: the 1st character 4 is the Section (Measurement and Monitoring); the 2nd character A is the Body System (Physiological Systems); the 3rd character 1 is the Operation (Monitoring); the 4th character 2 is the BodySystem (Cardiac); the 5th character X is the Approach (External); the 6th character 4 is the Function/Device (Electrical Activity); the 7th character Z is the Qualifier (No Qualifier).

What is the ICD-9-PCS equivalent of 4A12X4Z?

Under the General Equivalence Mappings, Monitoring of Cardiac Electrical Activity, External Approach crosswalks to ICD-9-PCS 89.54 (Electrographic monitoring) and 89.57 (Apexcardiogram (with ECG lead)). The mapping is approximate, so confirm it fits the documentation.